In the assembly of electronics or the mounting process of electronic parts, solder bonding has been widely used as a means for joining electronic parts to the circuit wiring. However, in recent years, due to environmental issues, attempts to suppress the use of harmful substances is gaining momentum. The suppression of lead contained in solder is being actively studied and the use of lead-free solder is being sought.
On the other hand, as a joining method that does not utilize solder, there is a method of using conductive adhesives. As a means for conductive adhesive, the Anisotropic Conductive Film (ACF) is known (for example, see Non-patent Document). By adding pressure, the conductive particles in the film come in physical contact, thereby expressing conductivity, and the binder resin bears the adhesive function. Further, a conductive adhesive, in which part of the surface of the conductive particle dissolves during thermocompression to integrate the conductive particles, is disclosed (for example, see Patent Document 1).